Problem: Subtract. $\dfrac{8}{5} - \dfrac{2}{10} = $
Explanation: Before we can subtract our fractions, they need to have the same denominator. $\frac{1}{5}$ $\frac{1}{5}$ $\frac{1}{5}$ $\frac{1}{5}$ $\frac{1}{5}$ $\frac{1}{5}$ $\frac{1}{5}$ $\frac{1}{5}$ $\frac{1}{5}$ $\frac{1}{5}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\frac{1}{10}$ $\dfrac{8}{5}$ $\dfrac{2}{10}$ $\dfrac{8}{5}-\dfrac{2}{10}$ Let's look at the multiples of each denominator and see which multiples they have in common. Denominator Multiples ${5}$ $5, \underline{10}, 15$ $10}$ $ \underline{10}, 20, 30$ The least common denominator is ${10}$. Let's use multiplication to make each fraction have a denominator of $10$. ${\dfrac{8}{5}}=\dfrac{{8} \times {2}}{{5} \times {2}} = {\dfrac{16}{10}}$ Now, we can subtract ${\dfrac{16}{10}} - \dfrac{2}{10}}$. $\dfrac{16}{10}$ $\dfrac{2}{10}$ $\dfrac{16}{10} - \dfrac{2}{10}$ $=\dfrac{{16}-2}}{10}$ $= \dfrac{14}{10}$ ${\dfrac{8}{5}} - \dfrac{2}{10}} = \dfrac{14}{10}$ We can also write $\dfrac{14}{10}$ as $\dfrac{7}{5}$, or $1\dfrac25$.